1. Field
Embodiments of the present invention relate to a technology associated with an organic light emitting diode display and a driving method thereof.
2. Description of the Related Art
A display device is used as a display device of a personal computer, portable phone, or personal digital assistant (PDA) or a monitor of various information devices, and an LCD using a liquid crystal panel, an organic light emitting diode display using an organic light emitting diode, and a PDP using a plasma panel may be used as the display device. Among them, the organic light emitting diode display, which has an excellent emission efficiency, luminance, and viewing angle, and a fast response speed, has been spotlighted.
The organic light emitting diode display has a display area including a plurality of pixels on a substrate in a matrix form, and is configured to provide a display by connecting a scan line and a data line to each pixel and selectively applying a data signal to the pixel.
The organic light emitting diode displays may be divided into a passive matrix type and an active matrix type. The passive matrix type refers to a type driven by forming positive electrodes and negative electrodes which cross each other and supplying data to selected lines.
The active matrix type refers to a type which maintains a data signal switched by a switching transistor in a capacitor and which applies the data signal to a driving transistor so as to control a current flowing in an organic light emitting diode.
FIG. 1 is a diagram for describing a method of driving an organic light emitting diode display in a general active matrix type.
Referring to FIG. 1, one frame comprises sub-frames of a left-eye image section (or period) LI and a right-eye image section (or period) RI to display a stereoscopic image. The left-eye image section LI comprises a scan section (or period) LN1 for inputting (or writing) left-eye image data and a light emitting section (or period) LE1 in which light is emitted according to the input left-eye image data. Further, the right-eye image section RI also comprises a scan section (or period) RN1 for inputting (or writing) right-eye image data and a light emitting section (or period) RE1 which emits light in which light is emitted according to the input right-eye image data.
As described above, at least each scan period and each light emitting period are required to express the left-eye image and the right-eye image for one frame (60 Hz), so that each of the sections should be processed at a speed of ¼ frame (240 Hz).
Further, with respect to all of the pixels of the display panel, the scan period and the light emitting period are separated from each other. When an image is concurrently (e.g., simultaneously) displayed across all of the pixels during the light emitting period, it may be advantageous to improve a motion blur phenomenon or implement a stereoscopic image. However, it is difficult to express accurate luminance because the light emitting period is limited to a half frame or shorter.
Accordingly, even not in a case of the driving of the stereoscopic image, light emitting luminance should be maximally increased to secure average luminance, thereby increasing a power voltage and power consumption. Further, because a driving current is also increased when the light is emitted, non-uniformity in the luminance due to a voltage drop (IR drop) may also be relatively increased.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.